A clamping device of this type is known, for example, from the Swiss Pat. No. 632 064. It is used for the assembly of frameworks consisting of vertical supports and horizontal beams. A clamping device is located at each end of a horizontal beam, the head of the retaining pin being introduced into a longitudinal groove in one of the horizontal beams. By means of the eccentric screw, the retaining pin is drawn inwards against the force of the spring in order to fix the beam onto the support.
The assembly of the clamping device is inconvenient because the retaining pin must be pressed into the bore of the insertion core and held until the eccentric screw is inserted. During the assembly of the framework, faulty handling can occur if the eccentric screw is rotated in the wrong direction so that its point releases the conical recess in the retaining pin and the latter is expelled from the insertion core by the spring.